"The Syrian government says 50 people were killed in Tremseh Thursday when its forces clashed with 'armed gangs' that were terrorizing village residents. The regime refers to its opponents as terrorists and gangsters. On Friday, the United Nations blamed government forces for the Tremseh assault, saying U.N. observers deployed near the village saw government troops using heavy weaponry and attack helicopters against it."

International condemnation of the alleged atrocity rose on Friday, as did the death toll, which Reuters is reporting is as high as 220 people.

Until this incident, operations of the U.N. mission in Syria had been suspended, but observers on the ground near Tremseh were "able to confirm shelling, helicopters in action and the presence of Syrian forces in Government checkpoints near Treimseh," Secretary General Ban Ki-moon said yesterday.

Ban said he was "outraged by reports of horrific mass killings," and called the attack a "clear violation" of the peace plan and international law.

As the BBC reports, the Syrian government says it was carrying out a military operation against rebel fighters and that no civilians were killed.

"Our correspondent says that, in contrast to the massacre at Houla two months ago, the opposition has not yet produced videos or a detailed lists of names of civilians killed.

"He says that activist and human rights groups have named a handful of civilians they say died in the bombardment of the village, but the few video postings they have produced, showing the bodies of young men, are consistent with the government line that many rebel fighters were killed."